Finding the Third Proportional to 142,940 and 210,128

Step by Step Solution

1. Step 1: Write the proportion equation
   142,940 : 210,128 = 210,128 : x
2. Step 2: Convert to fraction form
   142,940/210,128 = 210,128/x
3. Step 3: Cross multiply
   142,940x = 210,128 × 210,128
4. Step 4: Simplify right side
   142,940x = 44,153,776,384
5. Step 5: Solve for x
   x = 44,153,776,384/142,940
6. Step 6: Final answer
   x = 308,897.27